Efficiency Enhancement of Br-Based Perovskite Solar Cells Based on Localized Surface Plasmon Resonance with Mo@MoS ₂ Core–Shell Nanospheres

Carbon-electrode Br-based perovskite solar cells (PSCs) show potential application because of high open-circuit voltage and stability. Utilizing the localized surface plasmon resonance (LSPR) effect of metal–semiconductor core–shell nanostructures may alter the light absorption range of PSCs and enhance their short-circuit current density. In this study, an antisolvent-mediated strategy for interfacial modification at both perovskite grain boundaries and perovskite/carbon electrode interfaces was developed using Mo@MoS 2 core–shell nanospheres. By tuning the Mo:MoS 2 ratio, we achieved concurrent control of crystallization dynamics and photon management in MAPbBr 3 solar cells. The modified devices achieved significant improvements in external quantum efficiency within a wavelength range above 525 nm, showcasing improved spectral utilization. An average power conversion efficiency of 9.2% (best of 9.62%) was obtained with an optimized plasmonic effect, representing an improvement of 12% over reference cells. This work demonstrates the potential of LSPR core–shell nanostructures to unlock new efficiencies in stable, carbon-electrode perovskite photovoltaics by tailored interfacial and optical engineering.